diff options
| author | Phillip Potter | 2021-05-02 22:34:42 +0100 |
|---|---|---|
| committer | David S. Miller | 2021-05-03 13:33:54 -0700 |
| commit | 2e9f60932a2c19e8a11b4a69d419f107024b05a0 (patch) | |
| tree | c5fa8f27999183303b4c1394136a33388adb471c /net/hsr | |
| parent | f282df0391267fb2b263da1cc3233aa6fb81defc (diff) | |
net: hsr: check skb can contain struct hsr_ethhdr in fill_frame_info
Check at start of fill_frame_info that the MAC header in the supplied
skb is large enough to fit a struct hsr_ethhdr, as otherwise this is
not a valid HSR frame. If it is too small, return an error which will
then cause the callers to clean up the skb. Fixes a KMSAN-found
uninit-value bug reported by syzbot at:
https://syzkaller.appspot.com/bug?id=f7e9b601f1414f814f7602a82b6619a8d80bce3f
Reported-by: syzbot+e267bed19bfc5478fb33@syzkaller.appspotmail.com
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/hsr')
| -rw-r--r-- | net/hsr/hsr_forward.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c index b218e4594009..6852e9bccf5b 100644 --- a/net/hsr/hsr_forward.c +++ b/net/hsr/hsr_forward.c @@ -520,6 +520,10 @@ static int fill_frame_info(struct hsr_frame_info *frame, struct ethhdr *ethhdr; __be16 proto; + /* Check if skb contains hsr_ethhdr */ + if (skb->mac_len < sizeof(struct hsr_ethhdr)) + return -EINVAL; + memset(frame, 0, sizeof(*frame)); frame->is_supervision = is_supervision_frame(port->hsr, skb); frame->node_src = hsr_get_node(port, &hsr->node_db, skb, |